A recent survey stresses the need for better materials for maxillofacial prostheses. Answering this need, the present proposal describes a family of polymer alloys based on the chlorinated polyethylene polymers (CPE). The proposed alloys contain primarily heterogeneously chlorinated, high-density polyethylene, blended with other polymers such as polyethylene, polyvinyl chloride, polyvinyl alcohol, polyurethanes, hydrocarbon rubbers and ABS resins (acrylonitrile, butadiene, styrene). The CPE's have been found to alloy readily with the above-named generic classes. Two samples of CPE's have already been used by Gulf South Research Institute to produce prostheses; these polymers were found to be promising. The CPE's were moldable in existing equipment at relatively low temperatures. The resulting prostheses appeared very lifelike, and their thin peripheral edges exhibited high strength. Unlike polyvinyl chloride, the CPE's do not contain plasticizers which can migrate. They are more stable to ultraviolet light and to heat, and they readily accept intrinsic and external coloration. In toto, they appear to be superior to all existing prosthesis materials. The proposed study to select the more suitable alloys from this class of elastomers is a cooperative effort between Gulf South Research Institute and the Louisiana State University School of Dentistry in New Orleans. The study encompasses polymer blend formation, laboratory characterization and the clinical evaluation of the prostheses with a group of patients who have well-established histories.